In dentistry, vacuum systems are used to remove water, saliva, and debris from the patient's mouth. This fluid effluent often includes valuable materials such as amalgam from old amalgam fillings that are being removed. In Application Ser. No. 132,051 filed Mar. 20, 1980, now abandoned in favor of continuation Ser. No. 311,106 filed Oct. 13, 1981, the fluid effluent with its particulate matter was removed to a chamber comprising an upper vacuum layer and a lower liquid layer. The particles in the effluent would then settle to the bottom of the chamber. However, some of the finer particulate matter is held suspended in the liquid phase. In order to separate the liquid from this particulate matter, atomization of the fluid portion could be accomplished by various means enumerated in this first application. To sustain an even vacuum pressure on the oral cavity as well as on the upper portion of this chamber the upper gaseous layer should have an approximately constant volume. This is accomplished by introducing fluid particles free of particulate matter into the gaseous space where the outgoing vacuum duct removes this fluid portion from the upper layer into which it has been dispersed. Various means for accomplishing the dispersion of the fluid phase into the gaseous segment were designated in the earlier application. Among these were ultrasonic heads, as well as, conventional atomization means. The conventional atomization means would include a nozzle into which both air and fluid from the bottom of the chamber would be introduced. There are many mechanisms of increasing the dispersion of fluid propelled by air source such as stream splitters, spinning discs, and gratings. The air pressure source in the foregoing would have to be of such a relatively diminutive force that it would not interfere with the overall suction from oral cavity to the vacuum drainage.